An Indonesian national police official said three men had been detained in the investigation into a four-hour siege in the nation's capital Thursday that left seven people dead.
National police spokesperson Maj. Gen. Anton Charliyan said at a press conference Friday afternoon local time that the three men were not arrested but were taken for questioning and have not been directly linked to the bomb attack.
Earlier Friday, Col. Dwiyono, police chief in the Depok area, told Indonesia's MetroTV that three men had been arrested at dawn Friday at their homes on the outskirts of Jakarta, The Associated Press reported.
Photos: Gunfire and Blasts Rock Jakarta
Five of the seven people who were killed in the daylight assault Thursday were among the attackers, according to Indonesian officials. Twenty-four other people were injured as the attackers detonated explosives and battled police around a busy shopping area in downtown Jakarta.
Dwiyono — who, like many Indonesians, uses only one name — called the men suspected militants and said they were being questioned over possible links to the attacks.
ISIS claimed responsibility for the attacks in a statement issued through social media. It said its "soldiers" targeted Westerners from countries fighting the terrorist group in Iraq and Syria.
Charliyan said an ISIS flag was found at the crime scene. "It is confirmed that who is responsible is the fragment-splinter ISIS group," Charliyan told reporters.
Jakarta Police Chief Tito Karnavian also said the attackers had links with ISIS and were part of a group led by an Indonesian militant in Syria, The Jakarta Post reported Friday local time.
Charliyan said two of the five dead attackers were "recidivists" who previously had been engaged in radical activities. Charliyan said police have taken extra precautions to ensure their security in public places like airports and ports.